The field of the present disclosure relates generally to systems and methods for data reading and/or image capture, and more particularly but not exclusively to reading of optical codes such as, for example, barcodes.
Data reading devices are used to read optical codes, acquire data, and capture a variety of images. One common data reader device is an optical code reader. Optical codes typically comprise a pattern of dark elements and light spaces. There are various types of optical codes, including linear or 1-D (one-dimensional) codes such as UPC and EAN/JAN barcodes, 2-D (two-dimensional codes) such as MaxiCode codes, or stacked codes such as PDF 417 codes. For convenience, some embodiments may be described herein with reference to capture of 1-D barcodes, but the embodiments may also be useful for other optical codes and symbols as well as other images such as fingerprint capture.
One type of data reader is referred to as flying spot scanner wherein an illumination beam is moved (i.e., scanned) across the barcode while a photodetector monitors the reflected or backscattered light. For example, the photodetector may generate a high voltage when a large amount of light scattered from the barcode impinges on the detector, as from a light space, and likewise may produce a low voltage when a small amount of light scattered from the barcode impinges on the photodetector, as from a dark bar. The illumination source in spot scanners is a typically a coherent light source, such as a laser or laser diode, but may comprise a non-coherent light source such as light emitting diode. A laser illumination source may offer advantages of higher intensity illumination which may allow barcodes to be read over a larger range of distances from the barcode scanner (large depth of field) and under a wider range of background illumination conditions.
Another type of data reader is an imaging reader that employs an imaging device or sensor array, such as a CCD (charge coupled device) or CMOS (complementary metal oxide semiconductor) device. Imaging readers can be configured to read both 1-D and 2-D optical codes, as well as other types of optical codes or symbols and images of other items. When an imaging reader is used to read an optical code, an image of the optical code or portion thereof is focused onto a detector array. Though some imaging readers are capable of using ambient light illumination, an imaging reader typically utilizes a light source to illuminate the item being read, to provide the required signal response in the imaging device. A camera is typically a combination of a lens and an imaging device/sensor array, but the terms imager and camera will be used somewhat interchangeably herein.
An imager-based reader utilizes a camera or imager to generate electronic image data, typically in digital form, of an optical code. The image data is then processed to find and decode the optical code. For example, virtual scan line techniques are known techniques for digitally processing an image containing an optical code by looking across an image along a plurality of lines, typically spaced apart and at various angles, somewhat similar to the scan pattern of a laser beam in a laser-based scanner.
High performance optical code reading devices have evolved into a form typically requiring a large, tall (vertical) housing section to allow effective reading of the vertical faces of passing items. More recent development of more compact imaging-based readers has allowed the miniaturization of the protruding vertical housings, but still relies on some amount of enclosure height above the horizontal scanning surface in order to adequately cover codes near this plane. On the side opposite the operator (i.e., the customer side), the vertical housing section is distal from the operator and does not interfere with motion of items through the read region. Vertical housing extensions on the side of the reader proximate the operator have been proposed to provide a raised section providing a better/higher reading angle for reading sides of objects facing the operator.
For a standing operator, vertical features on the side of a scanning device proximate the operator (i.e., the checker side) typically do not interfere with the movement of items across the scanner because the operator's limbs are well above the scanning surface. The present inventor has recognized that for a seated operator, however, a significant protrusion above the horizontal surface in the area where they move their hands and arms can interfere with ergonomic movement of items across the data reader. Repetitive collisions of items or the operator's hands and arms with raised housing sections during the course of a duty shift can take a significant toll on the operator and may induce injuries. The present inventor has, therefore, determined that it would be desirable to provide a data reader that improves on the limitations of existing readers.